| 1. |
The amount of moisture in wood is ordinarily expressed as a percentage of the weight of the wood when oven dry.
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True |
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False |
| 2. |
The oven-drying method has been the most universally accepted method for determining moisture content, but it is slow and necessitates cutting the wood.
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True |
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False |
| 3. |
The electrical method of determining the moisture content of wood uses the relationships between moisture content and measurable electrical properties of wood, such as conductivity (or its inverse, resistivity), dielectric constant, or power loss factor.
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True |
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False |
| 4. |
What does ASTM stand for? |
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American Society for Testing and Materials |
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American Standards for Testing and Materials |
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American Standard for Testing and Mechanics |
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None of the above |
| 5. |
What does figure 12-1 illustrate about?
(Refer Pg 12-5)
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Recommended average moisture content for interior use of wood products in various areas of the United States |
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Equilibrium moisture content of wood |
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Recommended Moisture Content |
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None of the above |
| 6. |
The main purpose of air-drying lumber is to evaporate as much of the water as possible before end use or transfer to a dry kiln.
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True |
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False |
| 7. |
In kiln drying, higher temperatures and faster air circulation are used to decrease drying rate considerably.
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True |
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False |
| 8. |
Water in wood normally moves from high to low zones of moisture content, which means that the surface of the wood must be drier than the interior if moisture is to be removed.
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True |
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False
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| 9. |
The limitations of air-drying have led to increased use of technology that reduces drying time and introduces some control into drying from green to 20% to 25% moisture content. |
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True |
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False |
| 10. |
A kiln schedule is a carefully developed compromise between the need to dry lumber as fast as possible for economic efficiency and the need to avoid severe drying conditions that will lead to drying defects. |
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True |
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False |
| 11. |
Drying schedules vary by species, thickness, grade, and end use of lumber. There are two general types of kiln schedules: moisture content schedules and time-based schedules. |
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True |
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False |
| 12. |
Most drying defects or problems that develop in wood products during drying can be classified as fracture or distortion, warp, or discoloration. |
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True |
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False |
| 13. |
Distortion is any deviation of the face or edge of a board from flatness or any edge that is not at right angles to the adjacent face or edge.
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True |
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False |
| 14. |
Warp can be traced to two causes:(a) differences between radial, tangential, and longitudinal shrinkage in the piece as it dries or (b) growth stresses.
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True |
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False |
| 15. |
Shipping dry means lumber that has been partially dried to prevent stain or mold during brief periods of transit; ideally the outer 3.2 mm (1/8 in.) is dried to 25% or less moisture content.
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True |
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False |
| 16. |
Air dry means lumber that has been dried by exposure to the air outdoors or in a shed or by forced circulation of air that has not been heated above 49°C (120°F).
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True |
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False |
| 17. |
Kiln dry means lumber that has been dried in a kiln or by some special drying method to average moisture content specified or understood to be suitable for a certain use.
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True |
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False |
| 18. |
The normal seasonal changes in the moisture content of interior finish are not enough to cause serious dimensional change if the woodwork is carefully designed. |
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True |
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False |
| 19. |
Flooring is usually dried to the moisture content expected in service so that shrinking and swelling are maximized and buckling or large gaps between boards occur. |
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True |
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False |
| 20. |
When joist hangers are installed, the top of the joist should be above the top of the girder; otherwise, when the joist shrinks in the stirrup, the floor over the girder will be higher than that bearing upon the joist. |
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True |
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False |
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